Depression: Tests & Diagnosis

There are no
laboratory tests to diagnose depression. However, there are tests that can be
used to rule it out. Your doctor may perform blood work to check for other
conditions that could be contributing to your mood. Some medications and
illnesses, such as a viral infection, thyroid disorder, or significant hormonal
changes, can cause symptoms similar to depression.

If your doctor can
find no other cause for your symptoms, he or she may refer you to a licensed
mental health expert for evaluation.

Depression Tests

Doctors
look for specific symptoms in order to determine if a person is suffering from
depression. Expect your therapist or doctor to ask in-depth questions about
your mood, behavior, and day-to-day activities. You will also be asked about
your family’s psychological history. You will likely be asked to complete a
depression-rating questionnaire. This can help gauge your level of depression.

Examples
of such questionnaires include:

Beck Depression Inventory

The
Beck Depression Inventory (BDI) is made up of 21 self-reported depression
questions. They are designed to help mental health professionals assess the
mood, symptoms, and behaviors of people who are depressed. Each answer is given
a score of zero through three to indicate severity of symptoms.

Hamilton Depression Rating Scale

The
Hamilton Depression Rating Scale (HDRS) is a questionnaire designed to help
healthcare professionals determine the severity of depression in patients who
have already been diagnosed. It also consists of 21 questions; each relates to
a particular sign or symptom of depression. Multiple-choice answers are given a
score of zero through four. Higher total scores indicate more severe
depression.

Zung Self-Rating Scale for Depression

The Zung Scale is a
screening tool used to help assess the level of depression in depressed
patients. It is a 20-question test that provides a score range from 20 to 80.
Most depressed patients score between 50 and 69. A score above that indicates a
severe depression.

Depression Diagnosis

To be diagnosed with
depression, a patient must display five of the following symptoms for at least
two weeks:

sadness
or depressed mood

lack
of interest or pleasure in almost all activities, especially those that used to
be pleasurable

trouble
sleeping or sleeping all the time

fatigue
or lack of energy

feelings
of worthlessness and guilt

an
inability to concentrate or focus

change
in appetite

agitation
or feelings of moving in slow motion

recurring
thoughts of death

There are different
types of depression. Some are seasonal affective disorder (SAD), postpartum
depression, atypical depression, dysthymia (a type of chronic depression in
which a person’s moods are consistently low), and cyclothymia (a mild form or
bipolar disorder). Determining what type you have can help your doctor
determine the best treatment for your specific needs.